CVE-2022-49797 tracing: kprobe: Fix potential null-ptr-deref on trace_event_file in kprobe_event_gen_test_exit()

In the Linux kernel, the following vulnerability has been resolved: tracing: kprobe: Fix potential null-ptr-deref on traceeventfile in kprobeeventgentestexit When tracegeteventfile failed, genkretprobetest will be assigned as the error code. If module kprobeeventgentest is removed now, the null...